Primitive Silverfish vs Common Bark Louse

Side-by-side species comparison

Attribute Primitive Silverfish Common Bark Louse
Scientific Name Tricholepidion gertschi Graphopsocus cruciatus
Order Zygentoma Psocoptera
Family Lepidotrichidae Stenopsocidae
Size 8-12 mm 3-4 mm
Habitat Forests Woodlands
Diet Wood Feeders Wood Feeders
Regions United States Europe, North America
Conservation Near Threatened Least Concern

Primitive Silverfish

The most primitive living silverfish, restricted to old-growth forests of northern California. It retains compound eyes and other ancestral features.

💡

Did You Know?

It is considered a living fossil and the sole surviving member of its family.

Common Bark Louse

A winged bark louse with distinctive cross-shaped wing markings found on tree trunks across Europe. It feeds on algae and lichen on bark.

💡

Did You Know?

Its cross-shaped wing pattern makes it one of the easiest bark lice to identify.